Fetching just the Key/id from a ReferenceProperty in App Engine

Question

I could use a little help in AppEngine land...

Using the [Python] API I create relationships like this example from the docs:

class Author(db.Model):
           


        

Answer 1

Answering my own question for the sake of helping fellow searchers...

As suspected calling story.author.key().id() or even story.author.id() will result in datastore queries. The correct method dictated by the API docs is:

story = db.get(story_key)
author_id = Story.author.get_value_for_datastore(story).id()